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What is energy and what is fuel?
Energy is power derived from the use of physical or chemical resources, especially to provide light and heat or to work machines. Types of energy can include biomass energy, renewable energy, solar energy, fossil fuel energy, nuclear energy, etc.
A fuel is a material that stores energy in forms that can be released and used for work or as heat energy. Types of fuel include biomass, charcoal, coal, biogas, ethanol, LPG, solar, etc.
In humanitarian contexts, access to energy and fuels is largely considered to be an intersectional issue that affects individuals, households, and institutions.
At the individual and household level, energy is used for cooking, boiling water, lighting, heating and cooling homes, and powering appliances like televisions and refrigerators. The collective term for all of these uses is household energy.
Energy also has uses at the institutional level, some of which include refrigeration of vaccines, cooking school meals, lighting in health clinics and schools, street lighting in camps to encourage safe movement, and sustaining certain types of livelihoods such as drying fish, cooking meals for street vendors, and milling wheat or grain.
There are numerous fuel types that are used by crisis-affected populations and/or supported by humanitarian organizations. Each fuels comes with its own unique set of opportunities and challenges:
- Biomass—Biomass refers to organic material (living or recently living) from plants and animals, including agricultural and municipal solid waste products.1 Wood is still the largest biomass energy resource today, though other sources of biomass include food crops, grassy and woody plants, residues from agriculture or forestry, and the organic component of municipal and industrial wastes. Biomass can be transformed into different forms of bioenergy using low tech and high tech approaches. They can be simply processed into biomass pellets or briquettes or converted to liquid or gas fuels like ethanol through more advanced chemical processes.
- Charcoal—Charcoal is light black residue consisting of carbon, or any remaining ash, that results from removing water and volatile contents from animal and vegetation substances during the production process. It is produced by heating wood or other substances in the absence of oxygen.
- Coal—Coal is a black, solid, carbon-rich material found underground and is among the most important fossil fuels. In the household energy sector, coal is often used in countries where cooking and heating are combined, particularly in China.
- Biogas—Biogas is produced when biomass decomposes in an oxygen-free environment; a process called anaerobic digestion. It is a methane rich gas that can be generated from organic material such as animal and kitchen wastes, as well as some crop residues. For cooking and other thermal household tasks, biogas can be used directly in conventional low-pressure gas burners. Biogas is used for many different applications worldwide. In rural communities, small-scale digesters can provide biogas for single-household cooking and lighting. Large-scale digesters can utilize biogas for electricity production, heat and steam, chemical production, and vehicle fuel.
- Ethanol—Ethanol is a clean liquid biofuel that can be made from a variety of feedstocks (biomass that can be converted into biofuels and bioenergy) including sugary materials such as sugar cane, molasses, sugar beet, or sweet sorghum, starchy materials such as cassava (manioc), potatoes, or maize, or cellulostic materials such as wood, grasses, corn stover and other agricultural residues. Many new feedstocks are under development, such as algae, kelp and other wild or non-cultivated crops such as cattails (bulrush).
- Kerosene—Kerosene, also called paraffin in some countries, is a liquid product of crude oil with a high energy density. Kerosene is widely used in urban households for cooking, heating, and lighting, but is flammable and causes a high number of fires and deaths each year. Kerosene is sometimes improperly stored in soda bottles leading to accidental poisoning of children.
- Liquefied petroleum gas (LPG)—Liquefied Petroleum Gas (LPG) is a clean-burning, portable, sustainable, and efficient fuel. LPG is a co-product of natural gas and crude oil production and usually consists of a mixture of propane and butane for standard heating and cooking purposes. Its unique properties make it a versatile energy source—it is a multi-purpose energy with many applications, is portable, and can be used virtually anywhere in the world.
- Pellets or Briquettes/cakes—Raw biomass can sometimes come in forms that are not as convenient to burn such as sawdust, wood chips, grass, urban waste wood, agricultural residues. Processing the biomass into pellets or briquettes allows the biomass to burn more efficiently and evenly. Pellets or briquettes/cakes made from biomass such as agricultural waste, recycled materials, or other materials such as saw dust by applying pressure, heat and a binding agent (such as starch) to loose biomass residues or waste, to produce compact solid blocks of different sizes and shapes. They can be made manually or with a machine and often include a drying step to get rid of the water so that briquette is strong enough to be used in the same burning capacity as charcoal. There are two different types of briquettes; carbonized fuel briquettes which are made from waste materials that have undergone carbonization (the conversion of organic substances into carbon in the absence of oxygen) such as charcoal dust; and non-carbonized fuel briquettes which are produced from waste materials that are not carbonized (the raw material is partially decomposed and then dried_ such as saw dust and waste paper. Pellets are produced by compressing (known as densifying) organic material, generally some form of woody biomass, under intense pressure.
- Solar—A solar cooker is a device that uses the energy of direct sunlight to heat or cook food. They broadly fall into two categories; passive or active. Active solar technologies include the use of photovoltaic panels and solar thermal collectors to harness the energy; passive solar technologies including orienting the technology towards the sun and selecting materials with thermal mass or light dispersing properties. There are many different kinds of solar cookers but most follow the same basic principle of concentrating sunlight, converting light to heat or trapping the heat.
Last updated: 09/06/2021